Asymptotic Behavior of Traveling Wave Solutions to Reaction-Diffusion Equations

We will discuss travelling wave solutions to reaction-diffusion equations of the form: ut=uxx+ up (1-uq) which can be used as a mathematical model for various biological phenomena, as well as to model problems in combustion theory. We identify conditions on the wave speed so that travelling wave solutions exist for the case p ≥1 and q ≥1. Moreover, we estimate the rate of decay of the travelling wave solutions. When p \u3e 1 and q ≥1, this estimate requires center manifold theory because the typical linear methods fail to work. Through the mathematical analysis of reaction diffusion equations, the results of this research create further studies and application in physical and industrial chemistry

Dundee Discussion Papers in Economics 126:Efficiency wages, unemployment and macroeconomic policy

We provide empirical evidence from a number of European countries, which shows that unemployment and output are positively related when unemployment is low and inversely related when unemployment is high. We then construct a stylised macro-model with goods and labour market imperfections to show that the economy can rationally operate at an inefficient equilibrium in the neighbourhood of which the relationship between output and unemployment is positive. Our results suggest that circumstances exist in which market imperfections pose serious obstacles to the smooth working of expansionary and/or stabilization policies whose final aim is to improve welfare. KEYWORDS: Efficiency wages; effort supply; monopolistic competition; multiple equilibria; stability; fiscal multiplie

Measuring quality in social care services: theory and practice

Measuring and assessing service quality in the social care sector presents distinct challenges. The 'experience' good properties of social care, for instance, and the large influence played by subjective judgements about the quality of personal relationships between carer and user and of process-related service characteristics make it difficult to develop indicators of service quality, including those of service impact on final outcomes. Using some of the key features of the 'Production of Welfare' approach, the paper discusses recent developments in the UK of the theoretical and practical frameworks used for assessing quality in social care and for understanding the final impact of services on the wellbeing of their recipients. Key current and future challenges to the development of such frameworks include difficulties in disentangling the impact of social care services on final outcomes from the often dominating effects of other, non-service related factors, and the generalization of consumer-directed care models and of the 'personalization' of care services. These challenges are discussed in the context of the different possible applications of quality indicators, including their role as supporting the service commissioning process and their use for assessing the performance of service providers

Estimated General Equilibrium Models for the Evaluation of Monetary Policy in the US and Europe

A persistent criticism of general equilibrium models of monetary policy which incorporate nominal inertia in the form of the New Keynesian Phillips Curve (NKPC) is that they fail to capture the extent of inflation inertia in the data. In this paper we derive a general equilibrium model based on optimising behaviour, but which also implies a data consistent NKPC. Specifically our model accounts for nominal inertia in both price and wage setting as well for habits in consumption. Using US and European data from 1970 to 1998 our parameter estimates reveal that (i) there is relatively more inertia in price-setting in Europe; (ii) wage contracts last longer in the US; (iii) the extent of backward-looking behaviour in price and wage setting is statistically significant but small in both the US and Europe; and (iv) significant habits effects are present in European consumption. Finally we simulate the effects of monetary policy and find that while the magnitude of the impact of monetary policy on the endogenous variables in our estimated models are similar to other econometric studies, the dynamic paths for variables display less inertia than is typically found in studies which use output gaps to proxy changes in marginal costs.

Vertical Product Differentiation and the Import Demand Function: Theory and Evidence

In this paper we use a model of vertical product differentiation to cast doubt on the general validity of the import demand function as specified in macroeconomic models. The empirical importance of our theoretical concerns is then examined with the aid of two hypotheses. According to the first hypothesis, an increase in domestic wages is expected to reduce the share in total imports for goods in which the domestic comparative advantage is in high quality varieties of these goods. The second hypothesis states that an increase in non-wage income will increase the share of a good?s imports if the country has comparative advantage in high quality varieties of this good. We find considerable empirical support for both hypotheses in the data for Germany, Japan and the United States.

Do excessive wage increases raise imports? Theory and evidence.

wages, imports, vertically differentiated products